A Macintosh Plus emulator running on the Waveshare ESP32-S3-Touch-LCD-2.8B board. Mouse and keyboard input via BLE (Web Bluetooth) with a standalone web UI featuring trackpad, click button, and virtual keyboard.
Based on Spritetm's minimacplus, adapted for ESP32-S3 with OPI PSRAM and a 480x640 ST7701 RGB display.
- Board: Waveshare ESP32-S3-Touch-LCD-2.8B
- CPU: ESP32-S3 dual-core 240MHz
- RAM: 512KB SRAM + 8MB OPI PSRAM
- Flash: 16MB
- Display: 480x640 ST7701 RGB LCD
- Storage: MicroSD card slot (FAT32, SDMMC 1-bit mode)
- Musashi 68000 CPU emulator running at ~5.5MHz (~70% of native 7.83MHz)
- 4MB Mac RAM in OPI PSRAM (direct memory-mapped, no cache layer)
- NCR 5380 SCSI with HD from SD card or flash partition
- VIA 6522, Zilog 8530 SCC, IWM (stub)
- Display rotated 90° CW, 1:1 pixel mapping (640x480 patched ROM on 480x640)
- Boot status messages on screen
- PRAM saved to NVS
- BLE GATT server for keyboard/mouse input via Web Bluetooth
- Standalone web UI (
web/index.html) with trackpad, click button, and virtual keyboard
The emulator supports booting from a MicroSD card (preferred) or flash partitions (fallback). SD card gives true read/write support for the hard disk image — changes are saved.
Format a MicroSD card as FAT32 and place these files on it:
| File | Size | Description |
|---|---|---|
macplus.rom |
128KB | Mac Plus ROM |
hd.img |
any | SCSI hard disk image (writable) |
Insert the card and boot. The emulator loads ROM and HD from the SD card automatically.
If no SD card is present, the emulator falls back to flash partitions:
| Name | Offset | Size | Purpose |
|---|---|---|---|
| factory | 0x10000 | 1.5MB | Application |
| rom | 0x190000 | 128KB | Mac Plus ROM |
| hd | 0x1B0000 | ~14.3MB | SCSI Hard Disk |
esptool.py write_flash 0x190000 macplus.rom
esptool.py write_flash 0x1B0000 hd.imgNote: flash partition writes require erase cycles and are limited to ~14.3MB.
pio run -t uploadEither place macplus.rom and hd.img on a FAT32 MicroSD card, or flash them to partitions (see above).
A proper SCSI HD image with Apple partition map and driver is required. Raw HFS/floppy images (from Mini vMac, etc.) will NOT work.
Use MAME to create one:
# Create blank HD (1.4MB, 2800 blocks)
dd if=/dev/zero of=hd.img bs=512 count=2800
# Boot MAME with System floppy + blank HD
mame macplus -window -flop1 system6.dc42 -hard1 hd.img
# In MAME: use Apple HD SC Setup to initialize, then install SystemThe web UI is a standalone HTML file at web/index.html. It connects to the ESP32 over BLE using the Web Bluetooth API.
Requirements:
- Chrome (Android, Windows, macOS, Linux) or Edge — Safari and Firefox do not support Web Bluetooth
- The page must be served over HTTPS or from localhost (Web Bluetooth requirement)
A hosted version is available at https://memention.com/esp32_mac/
To use:
- Open the hosted version above, or serve
web/index.htmlyourself - Open the page in Chrome on your phone/computer
- Tap the gear icon and select Reconnect BLE
- Select MacPlus from the browser's Bluetooth pairing dialog
The web UI provides:
- Trackpad — touch and drag to move the Mac cursor
- Click button — tap for a single click; long press (~400ms) to lock the button down for dragging, tap again to release
- Virtual keyboard — tap the keyboard icon to show/hide a full Mac M0110A layout
- Modifier keys (Shift, Ctrl, Opt, Cmd) are sticky: tap to activate, auto-release after the next key
- Caps Lock is a true toggle: tap to engage, tap again to disengage
- Settings (gear icon) — reconnect/disconnect BLE
The MicroSD card shares SPI pins with the LCD init (freed after display setup):
| Signal | Pin | Notes |
|---|---|---|
| CLK | GPIO2 | Shared with LCD SPI CLK |
| CMD | GPIO1 | Shared with LCD SPI MOSI |
| D0 | GPIO42 | SD data line |
| DAT3 | EXIO4 | IO expander, pulled high |
Uses SDMMC 1-bit native mode (not SPI mode).
- minimacplus by Jeroen Domburg (Spritetm)
- Musashi 68K emulator by Karl Stenerud